Solve Complex Fraction Division: 15/3 ÷ (12/8 ÷ (1⅘ ÷ 8))

Complex Fraction Division with Mixed Numbers

153:(128:(145:8))=? \frac{15}{3}:(\frac{12}{8}:(1\frac{4}{5}:8))=\text{?}

❤️ Continue Your Math Journey!

We have hundreds of course questions with personalized recommendations + Account 100% premium

Step-by-step video solution

Watch the teacher solve the problem with clear explanations
00:00 Solve
00:03 Let's solve 15 divided by 3
00:08 Let's factor 12 into 4 and 3
00:11 Let's factor 12 into 4 and 2
00:23 Convert the whole number to fraction
00:27 Always solve parentheses first, the rule applies inside parentheses too
00:31 Simplify what's possible
00:40 Division is also multiplication by reciprocal (8 becomes one-eighth)
00:46 Division is multiplication by reciprocal
00:54 Make sure to multiply numerator by numerator and denominator by denominator
01:04 Division is multiplication by reciprocal
01:21 Simplify what's possible
01:25 Let's factor 9 into 3 and 3
01:34 Simplify what's possible
01:41 Let's factor 8 into 2 and 4
01:44 Simplify what's possible
01:47 And this is the solution to the question

Step-by-step written solution

Follow each step carefully to understand the complete solution
1

Understand the problem

153:(128:(145:8))=? \frac{15}{3}:(\frac{12}{8}:(1\frac{4}{5}:8))=\text{?}

2

Step-by-step solution

We solve the first fraction exercise:

153=5 \frac{15}{3}=5

We solve the second fraction by breaking it down into smaller multiplication exercises:

128=4×34×2=32 \frac{12}{8}=\frac{4\times3}{4\times2}=\frac{3}{2}

We convert the third fraction into a simple fraction:

145=95 1\frac{4}{5}=\frac{9}{5}

Now we obtain the exercise:

5:(32:(95:8))= 5:(\frac{3}{2}:(\frac{9}{5}:8))=

We note in inner parentheses the division exercise, a multiplication exercise between fractions:

5:(32:(95×18))= 5:(\frac{3}{2}:(\frac{9}{5}\times\frac{1}{8}))=

5:(32:95×8)= 5:(\frac{3}{2}:\frac{9}{5\times8})=

Now we invert the fraction to create a multiplication exercise:

5:(32×5×89)= 5:(\frac{3}{2}\times\frac{5\times8}{9})=

We combine the multiplication exercises, since it's just a multiplication operation:

5:3×5×82×9= 5:\frac{3\times5\times8}{2\times9}=

Now we invert the fraction to create a multiplication exercise:

5×2×93×5×8= 5\times\frac{2\times9}{3\times5\times8}=

We add the 5 to the numerator of the fraction in the multiplication exercise:

5×2×93×5×8= \frac{5\times2\times9}{3\times5\times8}=

We simplify the 5 in the numerator and denominator:

2×93×8= \frac{2\times9}{3\times8}=

We break down the 8 into a smaller multiplication exercise:

2×93×2×4= \frac{2\times9}{3\times2\times4}=

We simplify the 2 in the numerator and denominator:

93×4= \frac{9}{3\times4}=

We break down the 9 into a smaller multiplication exercise:

3×33×4= \frac{3\times3}{3\times4}=

We simplify the 3 in the numerator and denominator:

34 \frac{3}{4}

3

Final Answer

34 \frac{3}{4}

Key Points to Remember

Essential concepts to master this topic
  • Order: Work from innermost parentheses outward systematically
  • Division Rule: Dividing by a fraction means multiply by its reciprocal
  • Check: Verify 34=0.75 \frac{3}{4} = 0.75 matches your decimal calculation ✓

Common Mistakes

Avoid these frequent errors
  • Working left to right instead of innermost parentheses first
    Don't solve 15/3 ÷ 12/8 first = wrong order of operations! This ignores the nested parentheses and gives incorrect results. Always start with the deepest nested operation: (1⅘ ÷ 8) first.

Practice Quiz

Test your knowledge with interactive questions

\( 100-(5+55)= \)

FAQ

Everything you need to know about this question

Why do I start with the innermost parentheses?

+

The order of operations requires you to solve parentheses first, and when they're nested, you work from the inside out. This ensures you get the correct result!

How do I convert 1⅘ to an improper fraction?

+

Multiply the whole number by the denominator, then add the numerator: 145=(1×5)+45=95 1\frac{4}{5} = \frac{(1 \times 5) + 4}{5} = \frac{9}{5}

What does the colon (:) symbol mean in this problem?

+

The colon (:) means division, just like the ÷ symbol. So 153:(128) \frac{15}{3}:(\frac{12}{8}) is the same as 153÷128 \frac{15}{3} ÷ \frac{12}{8}

Why do I flip the fraction when dividing?

+

Dividing by a fraction is the same as multiplying by its reciprocal. So a÷bc=a×cb a ÷ \frac{b}{c} = a \times \frac{c}{b} . This rule makes division problems much easier to solve!

How can I check if ¾ is the right answer?

+

Work through the problem step-by-step again, or convert to decimals: 34=0.75 \frac{3}{4} = 0.75 . You can also substitute back and verify each step of your calculation.

What if I get confused by all the nested operations?

+

Take it slow! Write out each step clearly, starting with the innermost parentheses. Use arrows or highlights to track which operation you're solving next.

🌟 Unlock Your Math Potential

Get unlimited access to all 18 Commutative, Distributive and Associative Properties questions, detailed video solutions, and personalized progress tracking.

📹

Unlimited Video Solutions

Step-by-step explanations for every problem

📊

Progress Analytics

Track your mastery across all topics

🚫

Ad-Free Learning

Focus on math without distractions

No credit card required • Cancel anytime

More Questions

Click on any question to see the complete solution with step-by-step explanations